Cancer risks in men who had children with different partners from the Swedish Family-Cancer Database

Area of Science:

• Epidemiology
• Oncology
• Reproductive Health

Background:

• Paternal reproductive history is an understudied factor in cancer risk.
• Previous research has not extensively explored the association between the number of female partners and cancer incidence in men.

Purpose of the Study:

• To investigate the association between the number of female partners a man has fathered children with and his subsequent cancer risk.
• To identify specific cancer types that show altered risk based on paternal reproductive history.

Main Methods:

• Utilized the Swedish Family-Cancer Database (1961-1998), linking paternal information with cancer diagnoses.
• Analyzed cancer risks in a cohort of 2.9 million men, encompassing 298,134 cancer cases.
• Employed statistical analysis to identify trends in cancer incidence based on the number of women with whom men had children.

Main Results:

• Increased cancer risks observed for upper aerodigestive tract, lung, urinary bladder, and esophageal cancers in men with multiple female partners.
• Decreased cancer risks noted for colon cancer, skin tumors (squamous cell, melanoma), nervous system tumors, endocrine gland tumors, myeloma, and non-Hodgkin's lymphoma.
• The study suggests a link between multiple partners and increased risk of smoking/alcohol-related cancers, and decreased risk of other cancers possibly due to protective lifestyle factors.

Conclusions:

• Paternal reproductive history, specifically the number of female partners, is associated with differential cancer risks in men.
• Lifestyle factors, including smoking, alcohol consumption, diet, obesity, and physical fitness, may mediate these observed cancer risk trends.
• Further research is needed to elucidate the complex interplay between reproductive behavior, lifestyle, and cancer etiology.